Color filter is an essential component of liquid crystal display, and the technology associated with color filter is key technology which must be in hand. The technical keys of color filters rely on the development of red, green, blue pigmented photosensitive resists and the coating process thereof. In accordance with the chemical reaction mechanism and the developing principles of photosensitive resists, photosensitive resists can be divided into two classes, that is, negative and positive photosensitive resists. The negative photosensitive resists undergo chemical reaction to generate insoluble materials after light radiation. In contrast, the positive photosensitive resists per se are insoluble in certain solvents, but will become soluble materials after light radiation.
The coating principle of negative photosensitive resists involves: (1) a photosensitive resin (i.e., a photosensitive resist) is first coated onto the surface of an object to be processed, such as, glass substrate; (2) the resin coating is coated with a desired processing pattern (together with a masking plate), and then undergoes light exposure; (3) the exposed portion of the resin coating undergoes chemical crosslinking reaction so that the exposed and unexposed portion of the resin exhibit difference in terms of developing properties due to the change of their chemical structures. In other words, after light exposure and development with an appropriate developer, the unexposed portion is washed away, and the exposed portion is retained, thereby forming patterns oppose to the masking plate, and producing the negative photosensitive resists.
However, during the practical experiments and applications, it tends to find that rugged, unsmooth or caked phenomena appear on the surface of patterns formed by photosensitive resists after light exposure, development, or post-baking. Thus, there is a need of further researching and screening the components of negative photosensitive resist resin composition so as to address problems including surface defects and the like.